JPH06198178A - Catalyst for purification of exhaust gas - Google Patents

Catalyst for purification of exhaust gas

Info

Publication number
JPH06198178A
JPH06198178A JP4348904A JP34890492A JPH06198178A JP H06198178 A JPH06198178 A JP H06198178A JP 4348904 A JP4348904 A JP 4348904A JP 34890492 A JP34890492 A JP 34890492A JP H06198178 A JPH06198178 A JP H06198178A
Authority
JP
Japan
Prior art keywords
catalyst
oxide
exhaust gas
metals selected
hours
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP4348904A
Other languages
Japanese (ja)
Other versions
JP3161113B2 (en
Inventor
Hiroshi Akama
弘 赤間
Goji Masuda
剛司 増田
Hiroyuki Kanesaka
浩行 金坂
Naoki Kachi
直樹 可知
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nissan Motor Co Ltd
Original Assignee
Nissan Motor Co Ltd
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Filing date
Publication date
Application filed by Nissan Motor Co Ltd filed Critical Nissan Motor Co Ltd
Priority to JP34890492A priority Critical patent/JP3161113B2/en
Publication of JPH06198178A publication Critical patent/JPH06198178A/en
Application granted granted Critical
Publication of JP3161113B2 publication Critical patent/JP3161113B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Abstract

PURPOSE:To provide a catalyst acting effectively in fuel-air ratio near a stoichiometric region and in a lean region and having improved low temp. activity of a metal oxide-based catalyst. CONSTITUTION:One or two coating layers of an inorg. material based on activated alumina contg. one or more kinds of noble metals selected among Pt, Pd and Rh are formed on a honeycomb carrier and a coating layer of oxide of one-or more kinds of metals selected among Al, Zr, Si, Ti, Fe, V, Mn, Zn, Co, Cu, Cr, Mo, Sn, Ni and W is further formed on the one or two coating layers to obtain the catalyst for purification of exhaust gas.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、自動車エンジン等の内
燃機関の排気ガス浄化用触媒に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas purifying catalyst for an internal combustion engine such as an automobile engine.

【0002】[0002]

【従来の技術】従来、内燃機関からの排気ガスを浄化す
る触媒としては、一般に活性アルミナにパラジウム(P
d)、白金(Pt)およびロジウム(Rh)等の貴金属
成分を担持させたものが用いられている。このものは、
炭化水素(HC),一酸化炭素(CO)および窒素酸化
物(NOx)を同時に除去できることから、3元触媒と呼
ばれている。また、リーン(酸素過剰)領域におけるN
Oxの除去には、金属イオン交換ゼオライト、アルミ
ナ、ジルコニアおよびチタニア等各種金属酸化物から成
る触媒を用いるのが有効であることが知られている。
2. Description of the Related Art Conventionally, as a catalyst for purifying exhaust gas from an internal combustion engine, palladium (P
d), platinum (Pt), rhodium (Rh), and other noble metal components are used. This one is
It is called a three-way catalyst because it can remove hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) at the same time. In addition, N in the lean (excess oxygen) region
It is known that it is effective to use a catalyst composed of various metal oxides such as metal ion-exchanged zeolite, alumina, zirconia, and titania for removing Ox.

【0003】[0003]

【発明が解決しようとする課題】しかし、上記3元触媒
は、内燃機関をストイキ(通常走行時)領域に近い条件
で運転した場合にのみ有効であり、酸素含有量が多く、
より燃費が良好であるリーン領域で内燃機関を運転した
場合には、NOx除去活性の低下が避けられない。ま
た、上記金属酸化物系触媒は、ストイキ近傍において排
気ガス浄化性能を有さず、リーン領域においても低温活
性に劣り、またゼオライト系触媒は耐久性(耐熱性およ
び耐硫黄性)が十分でないという欠点があるために、実
用化に際して大きな障害となっている。
However, the above three-way catalyst is effective only when the internal combustion engine is operated under conditions close to the stoichiometric (normal driving) region, and has a large oxygen content.
When the internal combustion engine is operated in the lean range where the fuel consumption is better, a decrease in NOx removal activity cannot be avoided. Further, the metal oxide catalyst does not have exhaust gas purification performance in the vicinity of stoichiometry, is inferior in low temperature activity even in the lean region, and the zeolite catalyst has insufficient durability (heat resistance and sulfur resistance). Due to its drawbacks, it is a major obstacle to practical use.

【0004】このような背景から、ストイキ近傍のみな
らず、リーン領域でも排気ガスを効率良く浄化できる触
媒、特に低温活性および耐久性に優れた触媒が望まれて
いた。従って本発明の目的は、金属酸化物系触媒の低温
活性を改善し、かつストイキ近傍およびリーン領域にお
いて有効に作用する触媒を提供することにある。
From such a background, there has been a demand for a catalyst capable of efficiently purifying exhaust gas not only in the vicinity of stoichiometry but also in a lean region, particularly a catalyst excellent in low temperature activity and durability. Therefore, an object of the present invention is to provide a catalyst that improves the low temperature activity of a metal oxide catalyst and that works effectively in the vicinity of stoichiometry and in the lean region.

【0005】[0005]

【課題を解決するための手段】本発明の排気ガス浄化用
触媒は、ハニカム担体上に、白金、パラジウムおよびロ
ジウムから成る群から選ばれた1種以上の貴金属を含有
する活性アルミナを主成分とする無機物から成るコート
層(いわゆる3元触媒)を一層あるいは二層備え、その
上に、アルミニウム、ジルコニウム、ケイ素、チタン、
鉄、バナジウム、マンガン、亜鉛、コバルト、銅、クロ
ム、モリブデン、スズ、ニッケルおよびタングステンか
ら成る群から選ばれた1種以上の金属の酸化物から成る
コート層を備えて耐久性を向上させたことを特徴とす
る。この際、貴金属系の3元触媒としてPdを主活性成
分とした触媒を用いるのがより好ましい。
The exhaust gas purifying catalyst of the present invention comprises, on a honeycomb carrier, active alumina containing, as a main component, one or more noble metals selected from the group consisting of platinum, palladium and rhodium. One or two coat layers (so-called three-way catalysts) made of an inorganic substance are provided on which aluminum, zirconium, silicon, titanium,
Improving durability by providing a coating layer made of an oxide of at least one metal selected from the group consisting of iron, vanadium, manganese, zinc, cobalt, copper, chromium, molybdenum, tin, nickel and tungsten. Is characterized by. At this time, it is more preferable to use a catalyst containing Pd as a main active component as the noble metal-based three-way catalyst.

【0006】[0006]

【作用】次に作用を説明する。本発明の触媒は、リーン
領域においてNOx除去性能を有する金属酸化物触媒と
ストイキ近傍で排気ガス浄化能の高い3元触媒とを組み
合わせ、前者を上層部に、後者を内層部に塗布したもの
である。本発明者らは、この組み合わせ方を鋭意研究、
工夫した結果、上記の組み合わせとすることにより、単
なる貴金属系3元触媒と金属酸化物触媒との足し合わせ
以上の性能が得られることを見い出した。
[Operation] Next, the operation will be described. The catalyst of the present invention is a combination of a metal oxide catalyst having NOx removal performance in the lean region and a three-way catalyst having high exhaust gas purification ability in the vicinity of stoichiometry, the former being applied to the upper layer and the latter being applied to the inner layer. is there. The present inventors have diligently studied this combination method,
As a result of devising, it has been found that, by using the above combination, performance higher than mere addition of a noble metal-based three-way catalyst and a metal oxide catalyst can be obtained.

【0007】この詳細な機構は明らかではないが、次の
ように考えられる。リーン領域において、貴金属系触媒
はNOx除去性能の低下を起こすが、HCおよびCOの
浄化に対しては高活性を維持するため、HCおよびCO
の燃焼によって反応熱を発生する。この熱により、金属
酸化物触媒の温度が高まるため、より低い排気ガス温度
からNOx除去反応が進行するようになると同時に、N
Ox還元除去反応に有効なHCの部分酸化生成物が生
じ、より一層の高反応率が達成されるものと考えられ
る。貴金属系触媒として、Pdを主成分とする触媒を用
いると、より一層この効果は大きくなるので好ましい結
果が得られる。これは低温からのHCおよびCO燃焼活
性の立ち上がりが良好であるのに加え、HCの部分酸化
生成物が生じ易いためであろうと推定される。
Although the detailed mechanism is not clear, it is considered as follows. In the lean region, the noble metal catalyst deteriorates the NOx removal performance, but maintains high activity for purification of HC and CO.
The heat of reaction is generated by the combustion of. This heat causes the temperature of the metal oxide catalyst to rise, so that the NOx removal reaction proceeds from a lower exhaust gas temperature, and at the same time, N
It is considered that a partial oxidation product of HC, which is effective for the Ox reduction and removal reaction, is generated, and an even higher reaction rate is achieved. If a catalyst containing Pd as the main component is used as the noble metal-based catalyst, this effect will be further enhanced, so that favorable results can be obtained. It is presumed that this is because the rise of HC and CO combustion activity from a low temperature is good and a partial oxidation product of HC is likely to occur.

【0008】貴金属系触媒層と金属酸化物触媒層との組
み合わせ方を上記と逆にすると、金属酸化物触媒単味を
超えるNOx除去の反応率は得られない。この理由は、
HCおよびCO燃焼による反応熱の効果は得られるが、
NOxの還元除去反応に有効なHCの部分酸化生成物が
うまく生成しないためであると考えられる。
If the combination of the noble metal catalyst layer and the metal oxide catalyst layer is reversed from that described above, a reaction rate of NOx removal exceeding that of the metal oxide catalyst alone cannot be obtained. The reason for this is
Although the effect of reaction heat from HC and CO combustion can be obtained,
It is considered that this is because the partial oxidation product of HC, which is effective in the reduction and removal reaction of NOx, is not successfully produced.

【0009】本発明の触媒は、機能の異なる触媒を積層
した構造を有する。そのため、主としてハニカム形状で
の使用に供される。このハニカム材料としては、一般に
コージェライト質のものが多く用いられているが、これ
に限定されるものではなく、金属材料から成るハニカム
を用いることもでき、触媒そのものをハニカム形状に成
形することもできる。
The catalyst of the present invention has a structure in which catalysts having different functions are laminated. Therefore, it is mainly used for a honeycomb shape. As the honeycomb material, generally, a cordierite material is often used, but the honeycomb material is not limited to this, and a honeycomb made of a metal material can be used, and the catalyst itself can be formed into a honeycomb shape. it can.

【0010】[0010]

【実施例】本発明を実施例、比較例および試験例により
説明する。但し、溶液濃度および触媒担持量は、以下の
すべての実施例および比較例を通して一定である。 実施例1 γ−アルミナを主成分とする活性アルミナ粉末1000gに
対して、パラジウムが1.38重量%になるようにジニトロ
ジアンミンパラジウム水溶液を加え、よく攪拌した後、
乾燥器中120 ℃で8時間乾燥した。これを空気気流中で
400 ℃で2時間焼成した。このPd担持活性アルミナ14
00gをセリア(酸化セリウム:CeO2)936g、γ−
アルミナを主成分とする活性アルミナ320 g並びに硝酸
酸性ベーマイトゾル(ベーマイトの10重量%懸濁液に10
重量%の硝酸を添加することにより得られるゾル)2212
gと共にボールミルポットに投入し、8時間粉砕してス
ラリーを得た。このスラリーを、断面1平方インチあた
り約400 個の流路を有し、容量が1.7 Lである(以下1.
7 L、400 セル/in2 とする)コージェライト製のハニ
カムに第一層として塗布し、乾燥器中120 ℃で2時間乾
燥した後、空気気流中400 ℃で2時間焼成した。この際
の粉末塗布量は105 gであった。
EXAMPLES The present invention will be described with reference to Examples, Comparative Examples and Test Examples. However, the solution concentration and the catalyst loading amount are constant throughout all of the following examples and comparative examples. Example 1 To 1000 g of activated alumina powder containing γ-alumina as a main component, an aqueous dinitrodiamminepalladium solution was added so that the amount of palladium was 1.38% by weight, and after thoroughly stirring,
It was dried in a dryer at 120 ° C. for 8 hours. In the air stream
It was baked at 400 ° C. for 2 hours. This Pd-supported activated alumina 14
00 g of ceria (cerium oxide: CeO 2 ) 936 g, γ-
320 g of activated alumina mainly composed of alumina and nitric acid acidic boehmite sol (10% by weight of boehmite suspension)
Sol obtained by adding nitric acid in weight% 2212
It was put into a ball mill pot together with g and pulverized for 8 hours to obtain a slurry. This slurry has approximately 400 flow paths per square inch in cross section and has a volume of 1.7 L (see 1.
(7 L, 400 cells / in 2 ) was applied as a first layer to a cordierite honeycomb, dried in a dryer at 120 ° C. for 2 hours, and then fired in an air stream at 400 ° C. for 2 hours. The amount of powder applied at this time was 105 g.

【0011】次に、同様に、活性アルミナ粉末1000gに
対して、Rhが1重量%となるように、硝酸Rh水溶液
を加え、よく攪拌した後、乾燥、焼成し、Rhを担持し
たアルミナ粉末を得た。この粉末444 gを、活性アルミ
ナ粉末319 gおよび硝酸酸性ベーマイトゾル637 gと共
にボールミルポットに投入し、8時間粉砕してスラリー
を得た。このスラリーを、上記アルミナ担持Pd触媒が
塗布されたハニカム上に塗布量が37gになるように第二
層として塗布し、同様に乾燥し、焼成した。
Next, similarly, to 1000 g of activated alumina powder, an aqueous solution of Rh nitrate was added so that the Rh would be 1% by weight, well stirred, dried, and calcined to obtain an alumina powder carrying Rh. Obtained. 444 g of this powder was put into a ball mill pot together with 319 g of activated alumina powder and 637 g of nitric acid-acidic boehmite sol, and pulverized for 8 hours to obtain a slurry. This slurry was applied as a second layer on a honeycomb coated with the above Pd catalyst supporting alumina so that the coating amount was 37 g, and was similarly dried and fired.

【0012】一方、メタバナジン酸アンモニウムの水溶
液に酸化ジルコニウム(ZrO2 )粉末を浸せきし、約
2時間よく混合し、攪拌した後、120 ℃で24時間以上乾
燥した。得られた乾燥粉を大気中で550 ℃で2時間焼成
することにより、バナジウムの酸化物(V2 5 )を4.
2 重量%担持したZrO2 系触媒粉末を得た。この粉末
2250gを、シリカゾル(固形分20%)1250gおよび水15
00gと共にボールミルポットに投入し、4時間粉砕して
スラリーを得た。このスラリーを、上記の活性アルミナ
担持PdおよびRh触媒を塗布したハニカム上にさらに
塗布し、乾燥器中で120 ℃で2時間乾燥した後、空気気
流中で400 ℃で2時間焼成して焼き付けることにより触
媒(1) を得た。この際のV2 5 /ZrO2 系触媒の塗
布量は306 gであった。
On the other hand, zirconium oxide (ZrO 2 ) powder was dipped in an aqueous solution of ammonium metavanadate, mixed well for about 2 hours, stirred, and then dried at 120 ° C. for 24 hours or more. The vanadium oxide (V 2 O 5 ) was burned in the air at 550 ° C. for 2 hours to obtain 4.
A ZrO 2 -based catalyst powder supporting 2% by weight was obtained. This powder
2250 g, silica sol (solid content 20%) 1250 g and water 15
It was put into a ball mill pot together with 00 g and pulverized for 4 hours to obtain a slurry. The slurry is further applied onto the honeycomb coated with Pd and Rh catalyst supporting activated alumina described above, dried in a dryer at 120 ° C for 2 hours, and then baked and baked in an air stream at 400 ° C for 2 hours. Thus, a catalyst (1) was obtained. At this time, the coating amount of the V 2 O 5 / ZrO 2 based catalyst was 306 g.

【0013】実施例2 ZrO2 の代わりに酸化チタン(TiO2 )を用いた以
外は実施例1と同様にして、触媒(2) を得た。
Example 2 A catalyst (2) was obtained in the same manner as in Example 1 except that titanium oxide (TiO 2 ) was used instead of ZrO 2 .

【0014】実施例3 ZrO2 の代わりにアルミナ(Al2 3 )を用いた以
外は実施例1と同様にして、触媒(3) を得た。 実施例4 ZrO2 の代わりに酸化第二鉄(Fe2 3 )を用いた
以外は実施例1と同様にして、触媒(4) を得た。
Example 3 A catalyst (3) was obtained in the same manner as in Example 1 except that alumina (Al 2 O 3 ) was used instead of ZrO 2 . Example 4 A catalyst (4) was obtained in the same manner as in Example 1 except that ferric oxide (Fe 2 O 3 ) was used instead of ZrO 2 .

【0015】実施例5 メタバナジン酸アンモニウムの代わりにモリブデン酸ア
ンモニウムを用いることによりV2 5 を酸化モリブデ
ン(MoO3 )に代えた以外は実施例1と同様にして、
触媒(5) を得た。
Example 5 The procedure of Example 1 was repeated, except that V 2 O 5 was replaced with molybdenum oxide (MoO 3 ) by using ammonium molybdate instead of ammonium metavanadate.
A catalyst (5) was obtained.

【0016】実施例6 メタバナジン酸アンモニウムの代わりにパラタングステ
ン酸アンモニウムを用いることによりV2 5 を酸化タ
ングステン(WO3 )に代えた以外は実施例1と同様に
して、触媒(6) を得た。
Example 6 A catalyst (6) was obtained in the same manner as in Example 1 except that ammonium paratungstate was used instead of ammonium metavanadate to replace V 2 O 5 with tungsten oxide (WO 3 ). It was

【0017】実施例7 メタバナジン酸アンモニウムの代わりに硝酸コバルトを
用いることによりV25 を酸化コバルト(Co
3 4 )に代えた以外は実施例3と同様にして、触媒
(7) を得た。
Example 7 V 2 O 5 was converted to cobalt oxide (Co) by using cobalt nitrate instead of ammonium metavanadate.
3 O 4 ), except that the catalyst was used in the same manner as in Example 3.
I got (7).

【0018】実施例8 メタバナジン酸アンモニウムの代わりに硝酸銅を用いる
ことによりV2 5 を酸化銅(CuO)に代えた以外は
実施例3と同様にして、触媒(8) を得た。
Example 8 A catalyst (8) was obtained in the same manner as in Example 3 except that copper nitrate was used instead of ammonium metavanadate to replace V 2 O 5 with copper oxide (CuO).

【0019】実施例9 メタバナジン酸アンモニウムの代わりに硝酸スズを用い
ることによりV2 5を酸化スズ(SnO2 )に代えた
以外は実施例3と同様にして、触媒(9) を得た。
Example 9 A catalyst (9) was obtained in the same manner as in Example 3 except that tin nitrate was used instead of ammonium metavanadate to replace V 2 O 5 with tin oxide (SnO 2 ).

【0020】実施例10 メタバナジン酸アンモニウムの代わりに硝酸マンガンを
用いることによりV25 を酸化マンガン(Mn
2 3 )に代えた以外は実施例3と同様にして、触媒(1
0)を得た。
Example 10 V 2 O 5 was converted to manganese oxide (Mn by using manganese nitrate in place of ammonium metavanadate).
2 O 3 ), except that the catalyst (1
I got 0).

【0021】実施例11 メタバナジン酸アンモニウムの代わりに硝酸亜鉛を用い
ることによりV2 5を酸化亜鉛(ZnO)に代えた以
外は実施例3と同様にして、触媒(11)を得た。
Example 11 A catalyst (11) was obtained in the same manner as in Example 3 except that zinc nitrate was used instead of ammonium metavanadate to replace V 2 O 5 with zinc oxide (ZnO).

【0022】実施例12 メタバナジン酸アンモニウムの代わりに硝酸ニッケルを
用いることによりV25 を酸化ニッケル(NiO)に
代えた以外は実施例3と同様にして、触媒(12)を得た。
Example 12 A catalyst (12) was obtained in the same manner as in Example 3 except that nickel nitrate was used in place of ammonium metavanadate to replace V 2 O 5 with nickel oxide (NiO).

【0023】実施例13 メタバナジン酸アンモニウムの代わりに硝酸クロムを用
いることにより、V25 を酸化クロム(Cr2 3
に代えた以外は実施例4と同様にして、触媒(13)を得
た。
Example 13 V 2 O 5 was converted to chromium oxide (Cr 2 O 3 ) by using chromium nitrate instead of ammonium metavanadate.
A catalyst (13) was obtained in the same manner as in Example 4 except that the above was used.

【0024】実施例14 ZrO2 の代わりに酸化チタンとシリカの混合物である
TiO2 −SiO2 (TiO2 :SiO2 (モル比)=
5:3の混合物)を用いた以外は実施例1と同様にし
て、触媒(14)を得た。
Example 14 TiO 2 —SiO 2 (TiO 2 : SiO 2 (molar ratio) = a mixture of titanium oxide and silica instead of ZrO 2 =
A catalyst (14) was obtained in the same manner as in Example 1 except that a 5: 3 mixture) was used.

【0025】実施例15 γ−アルミナを担体としたPd−Rh系の3元触媒の代
わりにPt−Rh系の触媒を用いた以外は実施例1と同
様にして、触媒(15)を得た。
Example 15 A catalyst (15) was obtained in the same manner as in Example 1 except that a Pt-Rh-based catalyst was used instead of the Pd-Rh-based three-way catalyst using γ-alumina as a carrier. .

【0026】実施例16 ZrO2 粉末をメタバナジン酸アンモニウムの水溶液に
浸せきせず、そのまま実施例1と同様にスラリー化して
用いた以外は実施例1と同様にして、触媒(16)を得た。
Example 16 A catalyst (16) was obtained in the same manner as in Example 1 except that the ZrO 2 powder was not soaked in an aqueous solution of ammonium metavanadate and was slurried in the same manner as in Example 1.

【0027】実施例17 ZrO2 粉末の代わりにAl2 3 を用いた以外は実施
例16と同様にして、触媒(17)を得た。
Example 17 A catalyst (17) was obtained in the same manner as in Example 16 except that Al 2 O 3 was used instead of ZrO 2 powder.

【0028】比較例1 コージェライト製ハニカム基材(1.7 L,400 セル/in
2)に、γ−アルミナを担体としたPd−Rh系の3元触
媒440 gを塗布し、乾燥した後、電気炉で500℃、2時
間焼成することにより触媒(18)を得た。
Comparative Example 1 Cordierite honeycomb substrate (1.7 L, 400 cells / in
2 ) was coated with 440 g of a Pd-Rh-based three-way catalyst using γ-alumina as a carrier, dried, and then calcined in an electric furnace at 500 ° C for 2 hours to obtain a catalyst (18).

【0029】比較例2 実施例1で得たV2 5 /ZrO2 触媒を、コージェラ
イト製ハニカム基材(1.7 L,400 セル/in2)に塗布
(320 g/個−触媒)し、乾燥した後、電気炉で500
℃、2時間焼成することにより触媒(19)を得た。
Comparative Example 2 The V 2 O 5 / ZrO 2 catalyst obtained in Example 1 was applied (320 g / piece-catalyst) to a cordierite honeycomb substrate (1.7 L, 400 cells / in 2 ), After drying, 500 in an electric furnace
A catalyst (19) was obtained by calcining at ℃ for 2 hours.

【0030】比較例3 実施例7で調製したCo3 4 /Al2 3 触媒を、コ
ージェライト製ハニカム基材(1.7 L,400 セル/in2)
に塗布(310 g/個−触媒)し、乾燥した後、電気炉で
500 ℃、2時間焼成することにより触媒(20)を得た。
Comparative Example 3 The cordierite honeycomb substrate (1.7 L, 400 cells / in 2 ) was prepared from the Co 3 O 4 / Al 2 O 3 catalyst prepared in Example 7.
(310 g / piece-catalyst) and dry it in an electric furnace
A catalyst (20) was obtained by calcining at 500 ° C. for 2 hours.

【0031】比較例4 コージェライト製ハニカム基材(1.7 L,400 セル/in
2)に、実施例1で調製したV2 5 /ZrO2 触媒を31
0 g塗布し、次いでその上層に、同じく実施例1で調製
したγ−アルミナを担体としたPd−Rh系の3元触媒
130 gを塗布し、乾燥した後、電気炉で500 ℃、2時間
焼成することにより触媒(21)を得た。
Comparative Example 4 Cordierite honeycomb substrate (1.7 L, 400 cells / in
2 ) to the V 2 O 5 / ZrO 2 catalyst prepared in Example 1
0 g, and then on the upper layer, a Pd-Rh-based three-way catalyst similarly prepared in Example 1 using γ-alumina as a carrier.
After applying 130 g and drying, the catalyst (21) was obtained by baking in an electric furnace at 500 ° C. for 2 hours.

【0032】試験例 下記のエンジン排気ガスを用いた台上評価により、上記
の実施例および比較例の触媒のNOx除去性能を調べ
た。本試験例は表1に示した性能評価条件により実施し
た。表2に空燃比約20での実施例1〜17および比較例1
〜4の触媒の300〜550 ℃におけるNOx除去性能を示
す。表3にはストイキ(空燃比14.6) での実施例1、比
較例1および2の触媒の300 〜400 ℃におけるNOx除
去性能を示す。
Test Example The NOx removal performance of the catalysts of the above Examples and Comparative Examples was investigated by the bench evaluation using the following engine exhaust gas. This test example was carried out under the performance evaluation conditions shown in Table 1. Table 2 shows Examples 1 to 17 and Comparative Example 1 with an air-fuel ratio of about 20.
4 shows the NOx removal performance of the catalysts of .about.4 at 300 to 550.degree. Table 3 shows the NOx removal performance of the catalysts of Example 1 and Comparative Examples 1 and 2 under stoichiometry (air-fuel ratio 14.6) at 300 to 400 ° C.

【0033】[0033]

【表1】性能評価条件 触媒容量:1.7 L 空間速度:約12000 〜15000 h-1 触媒層入口温度:300 〜550 ℃(昇温温度(触媒入口温
度)=5℃/分) エンジン:サニー(日産自動車(株))用排気量1600 c
c (SCV) 燃料:無鉛レギュラーガソリン 平均空燃比(A/F):約20 炭化水素類(HC):窒素酸化物(NOx)=10:1〜
5:1 (但しHC濃度はC 1換算濃度) 平均空燃比(A/F):14.6 炭化水素類(HC):窒素酸化物(NOx)=1.6 :1
〜1.3 :1 (但しHC濃度はC 1換算濃度)
[Table 1] Performance evaluation conditions Catalyst capacity: 1.7 L Space velocity: Approximately 12000 to 15000 h -1 Catalyst layer inlet temperature: 300 to 550 ° C (temperature rise (catalyst inlet temperature) = 5 ° C / min) Engine: Sunny ( Displacement for Nissan Motor Co., Ltd. 1600 c
c (SCV) Fuel: Unleaded regular gasoline Average air-fuel ratio (A / F): Approximately 20 Hydrocarbons (HC): Nitrogen oxides (NOx) = 10: 1 to 1
5: 1 (However, HC concentration is C 1 conversion concentration) Average air-fuel ratio (A / F): 14.6 Hydrocarbons (HC): Nitrogen oxides (NOx) = 1.6: 1
~ 1.3: 1 (However, HC concentration is C 1 conversion concentration)

【0034】[0034]

【表2】 [Table 2]

【0035】[0035]

【表3】 [Table 3]

【0036】[0036]

【発明の効果】以上説明してきたように、本発明の触媒
は、ハニカム担体上に、白金、パラジウムおよびロジウ
ムから成る群から選ばれた1種以上の貴金属を含有する
活性アルミナを主成分とする無機物から成るコート層を
一層あるいは二層備え、その上に、アルミニウム、ジル
コニウム、ケイ素、チタン、鉄、バナジウム、マンガ
ン、亜鉛、コバルト、銅、クロム、モリブデン、スズ、
ニッケル、タングステンから成る群から選ばれた1種以
上の金属の酸化物から成るコート層を備えたことにより
耐久性が向上し、ストイキ近傍からリーン領域までの幅
広い空燃比で排気ガスを効率よく浄化することができる
ため、自動車の燃費改善の効果が大きい。
As described above, the catalyst of the present invention is mainly composed of activated alumina containing, on a honeycomb carrier, one or more noble metals selected from the group consisting of platinum, palladium and rhodium. One or two coat layers made of an inorganic material are provided, on which aluminum, zirconium, silicon, titanium, iron, vanadium, manganese, zinc, cobalt, copper, chromium, molybdenum, tin,
Durability is improved by having a coating layer consisting of oxides of one or more metals selected from the group consisting of nickel and tungsten, and exhaust gas is efficiently purified with a wide range of air-fuel ratios from near stoichiometric to lean regions. Therefore, the effect of improving the fuel efficiency of the automobile is great.

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.5 識別記号 庁内整理番号 FI 技術表示箇所 B01J 23/64 ZAB 8017−4G 102 A 8017−4G 104 A 8017−4G 23/89 ZAB A 8017−4G (72)発明者 可知 直樹 神奈川県横浜市神奈川区宝町2番地 日産 自動車株式会社内─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification code Internal reference number FI Technical indication location B01J 23/64 ZAB 8017-4G 102 A 8017-4G 104 A 8017-4G 23/89 ZAB A 8017- 4G (72) Inventor Naoki Kachi 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 ハニカム担体上に、白金、パラジウムお
よびロジウムから成る群から選ばれた1種以上の貴金属
を含有する活性アルミナを主成分とする無機物から成る
コート層を一層あるいは二層備え、その上に、アルミニ
ウム、ジルコニウム、ケイ素、チタン、鉄、バナジウ
ム、マンガン、亜鉛、コバルト、銅、クロム、モリブデ
ン、スズ、ニッケルおよびタングステンから成る群から
選ばれた1種以上の金属の酸化物から成るコート層を備
えたことを特徴とする排気ガス浄化用触媒。
1. A honeycomb carrier is provided with one or two coat layers made of an inorganic material whose main component is activated alumina containing one or more noble metals selected from the group consisting of platinum, palladium and rhodium. Coated with an oxide of one or more metals selected from the group consisting of aluminum, zirconium, silicon, titanium, iron, vanadium, manganese, zinc, cobalt, copper, chromium, molybdenum, tin, nickel and tungsten. An exhaust gas purifying catalyst characterized by having a layer.
JP34890492A 1992-12-28 1992-12-28 Exhaust gas purification catalyst Expired - Fee Related JP3161113B2 (en)

Priority Applications (1)

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JP34890492A JP3161113B2 (en) 1992-12-28 1992-12-28 Exhaust gas purification catalyst

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP34890492A JP3161113B2 (en) 1992-12-28 1992-12-28 Exhaust gas purification catalyst

Publications (2)

Publication Number Publication Date
JPH06198178A true JPH06198178A (en) 1994-07-19
JP3161113B2 JP3161113B2 (en) 2001-04-25

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Country Status (1)

Country Link
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6645439B2 (en) 1998-05-27 2003-11-11 Johnson Matthey Japan Ltd. Exhaust gas clean-up catalyst
US6933409B1 (en) 1999-05-13 2005-08-23 Symyx Technologies, Inc. Amination of aromatic hydrocarbons and heterocyclic analogs thereof
KR100681334B1 (en) * 2005-06-07 2007-02-09 희성엥겔하드주식회사 Catalytic composition for improving diesel oxidation activity
JP2007319795A (en) * 2006-06-01 2007-12-13 Nissan Motor Co Ltd Catalyst for purifying exhaust gas and its production method
JP2009255073A (en) * 2008-03-28 2009-11-05 Nissan Motor Co Ltd Exhaust gas cleaning catalyst
CN102909020A (en) * 2011-08-01 2013-02-06 中国石油化工股份有限公司 Sulfur-resistant catalytic-combustion catalyst and preparation method thereof

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Publication number Priority date Publication date Assignee Title
KR101921127B1 (en) 2012-02-29 2018-11-22 엘지이노텍 주식회사 Lighting device

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6645439B2 (en) 1998-05-27 2003-11-11 Johnson Matthey Japan Ltd. Exhaust gas clean-up catalyst
US6933409B1 (en) 1999-05-13 2005-08-23 Symyx Technologies, Inc. Amination of aromatic hydrocarbons and heterocyclic analogs thereof
KR100681334B1 (en) * 2005-06-07 2007-02-09 희성엥겔하드주식회사 Catalytic composition for improving diesel oxidation activity
JP2007319795A (en) * 2006-06-01 2007-12-13 Nissan Motor Co Ltd Catalyst for purifying exhaust gas and its production method
JP2009255073A (en) * 2008-03-28 2009-11-05 Nissan Motor Co Ltd Exhaust gas cleaning catalyst
CN102909020A (en) * 2011-08-01 2013-02-06 中国石油化工股份有限公司 Sulfur-resistant catalytic-combustion catalyst and preparation method thereof
CN102909020B (en) * 2011-08-01 2014-06-25 中国石油化工股份有限公司 Sulfur-resistant catalytic-combustion catalyst and preparation method thereof

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